Stroke is the leading cause of disability in the US, with 795,000 Americans suffering one each year. See Reference No. 1. All references are listed at the end of the specification. Traditional physical rehabilitation of the paretic arm involves passive movement, compensatory training on the less involved arm, electrical stimulation, to which more recently has been added constraint induced therapy to combat learned non-use of the hemiplegic hand. See Reference No. 2. These are uni-manual training approaches involving a single arm which do not take into account the prevalence of activities of daily living (ADLs) which involve both arms.
Another drawback of uni-manual training is diminished neural cross talk to mirror motor areas associated with bimanual activities. A meta analysis of 48 stroke studies to determine the cumulative effect of bilateral arm training on motor capabilities post-stroke (Reference No. 3) did however find a significant effect post-training involving bimanual repeated reach movements timed to auditory cues. Another argument in favor of bilateral training is a recent randomized controlled study of stroke patients at the end of their outpatient therapy. See Reference No. 4. Researchers found, for the first time, that training the healthy arm (in a peg-board filling task) resulted in a 23% functional improvement in the non-trained paretic arm. Researchers also observed improvement in bilateral tasks performance in the experimental group. The control group, which did not train, had no significant difference from baseline. These studies point to the untapped advantages of bimanual training and the present application.
It is known in the art that numerous task-related repetitions are needed to produce neural rewiring in the brain. Repetitions, while necessary to induce recovery through brain plasticity, can lead to a lack of engagement (attendance to task) by the patient due to boredom. Second only to the amount of practice, feedback on performance is a key element in motor training and a way to engage the patient. Knowledge of performance feedback can be provided by the therapist (present next to the patient), or through graphics in a virtual rehabilitation setting (Reference No. 5), where the therapist, may be remote. Virtual rehabilitation benefits focus, motivation, and provides intensive training without boredom.
Stroke survivors, as well as other patient populations (such as those post traumatic brain injury—TBI) present with both motor and cognitive deficits. See Reference No. 6. Typically their short term and long term memory are affected, as are decision making (executive function), and the ability to focus. Most stroke patients also get depressed. Under the current fractionated care system, such patients are attended by therapists, as well as psychologists or psychiatrists, and speech language pathologists in separate sessions. This care delivery method is costly and does not exploit fully the mind-body continuum. As opposed to patients who are post-TBI and predominantly young, the elderly form the majority of stroke survivors. For them, the situation worsens due to age related cognitive decline. See Reference No. 7.
One age-related cognitive deficit is diminished ability for split attention (or dual-tasking). These patients need a system designed from the start for integrative cognitive and motor therapy, in order to minimize costs and maximize outcomes. Such system would use therapeutic games that pose both cognitive and whole arm motor demands, and train grasping in dual tasks. The system should automatically adapt to the patient's functioning level, thus making games winnable, so to improve morale (reduce depression). Games, such as cognitive games, mediate many repetitions, so to facilitate improvement or at least maintenance of cognitive function over time. Users that benefit most are the elderly with mild cognitive impairments, precursor to full-blown dementia.
There are indications that bimanual training induces higher functional improvements compared to uni-manual training. A recent randomized controlled study (Reference No. 8) was performed on patients chronic post-stroke, half doing bimanual training and the controls doing training of the affected arm, with some coping mechanism (assistance) from the other arm. While both groups had the same training duration and intensity, those doing bimanual training had a 9 points larger improvement in motor function (as measured by their Fugl-Meyer Assessment [reference 9] scores) vs. controls. More recently a randomized study of 36 nursing home residents was performed to try to lessen cognitive decline and improve memory function. See Reference 10. The experimental group showed significant improvements in long-term recall and in several other aspects of cognition, while controls showed progressive decline. The above findings motivate the system described here, a bimanual therapy system that simultaneously addresses motor and cognitive impairments of patients post-stroke, post TBI, or those with Mild Cognitive Impairments (MCI) developing into dementia. This novel integrative therapy uses custom, adaptable, bimanual virtual reality games, which combine into gradated therapy sessions.
With the aging of the population the number of elderly affected by Dementia (including Alzheimer's disease) has grown significantly. In standard of care a clinician (typically a neuropsychologist, registered nurse, clinical social worker, or other medical professional) administers a standardized test which scores the individual's cognitive abilities.
An example of such standardized test is the Mini Mental State Exam (MMSE) (Reference No. 24) which scores cognitive ability or impairments on a scale of 0 (severely impaired) to 30 (normal cognition). This is a paper and pencil method, in which the clinician asks questions and scores the answers. These answers may involve orientation (determining place and time), arithmetic (subtractions by 7), writing a sentence, drawing after a given image, etc. The current method has major flaws:
First, it is dependent on individual's hearing. Typically the elderly are prone to hearing loss, and if not checked it can lead to miss diagnosis just because the person cannot hear the examiner's questions. Many elderly are wrongly diagnosed with Alzheimer's disease just because they have no working hearing aids.
Second, it requires a specialist to administer, and according to the Alzheimer's Association (Reference No. 26), more than 5 Million Americans are suffering from the ravages of this irreversible neurodegenerative disorder. Therefore there are just not enough qualified people to test them. This shortage will only grow with the increase in the number of people that require examination.
Third, there is a level of variability in the administration of the test, which may affect the outcome. An automated screening/assessment method would be preferable, as test administration is more uniform.
Fourth, if the patient has speech impairments, such as for those afflicted by Primary Progressive Aphasia, a rare form of dementia affecting men in their 40s and 50s, that their verbal responses to test questions may be not understood or wrongly interpreted by the examiner.
There is a need for a computerized screening system that can perform examinations, and use methods where the elderly's hearing and speech are less critical to get a more accurate result. A number of computerized diagnostic and therapy systems exist, including the web-based Lumosity (Reference No. 22). The limitation with these systems is that they are mouse-based, and uni-manual. Mouse interaction limits arm movement to a 2D plane, and uni-manual tasks are necessarily less complex/ecological than bimanual interactions. Thus the full potential of an individual's cognitive capacity may not be evaluated by these simplistic game simulations.